The duhem quine thesis

Consider, first, whether possessing evidence is sufficient for justified belief. Some think that justified belief is essentially a deontological notion, involving the fulfillment of one's duties or responsibilities as a believer. Hence, while having a belief that fits one's evidence might be implicated in responsible belief, it seems that responsibility also requires making proper use of one's evidence. For example, suppose I am justified in believing p , and that I am justified in believing that if p then q . Yet, I do not believe q on the basis of this evidence, but believe it simply because I like the way it sounds (Korblith, 1980). If I believe q on these grounds, I am arguably not justified in my belief, even though it "fits" my other beliefs; believing a proposition because of the way it sounds seems like a patently irresponsible and therefore unjustified belief, no matter what unused evidence for it I may possess. In defense of evidentialism here, Conee and Feldman appeal to the auxiliary notion of a well-founded belief: a belief that not only fits the evidence a person possesses, but is properly based upon it. Thus, in the above example, my belief in q is not well-founded, since I do not properly use my evidence, even though the belief is justified by the evidence I possess. This maneuver may do little, however, to placate those who take justified belief to be inextricably related to responsibility.